373 cards found matching energy cost is at least 4

Gentle Gemdragon
Gentlemen's Duel
Glasc Mixologist
Grand Strategem
Grumpy Rockbear
Guardian of the Passage
Gutter Palace
Harnessed Dragon
Harpoon Squad
Helm of Suppression
Herald of Scales
Herald of Spring
Hextech Disc
Highlander
Horns of the Dragon
Hostile Takeover
Hungry Wolf
Hwei, Brooding Painter
Iascylla
Icathian Rain
Illaoi, Prophet of the Great Kraken
Imperial Decree
Imposing Challenger
Inviolus Vox